HNK-1-defined antigen detected in paraffin-embedded neuroectoderm tumors and those derived from cells of the amine precursor uptake and decarboxylation system.

The reactivity of the HNK-1 monoclonal antibody that, besides a subset of hematopoietic cells with natural killer activity, also detects neuroectodermal cells, was screened on 153 human tumors. Immunoperoxidase staining of paraffin sections revealed that HNK-1 detects neuroectoderm-derived cancers and tumors with endocrine activity. Because the antigen detected by HNK-1 is well conserved in paraffin sections, this antibody is of potential diagnostic value in routine histopathology and might help to elucidate the histogenesis of some poorly understood tumors.